Fuel transfer device with underwater connection and emergency release mechanism

Abstract

The application provides a fuel transfer device with an underwater connecting mechanism and an emergency unlocking mechanism, comprising a track, a transfer channel and a transport trolley, the transfer channel and part of the track are arranged between a reactor building and a fuel building, the transport trolley is arranged on the track, and the application further comprises: a connecting trolley frame arranged on the track and closer to the reactor building than the transport trolley; a first connecting mechanism fixed on one side of the connecting trolley frame close to the transport trolley; a second connecting mechanism arranged on one side of the transport trolley close to the connecting trolley frame, the second connecting mechanism and the first connecting mechanism form a clamping connection when being docked; and an emergency unlocking mechanism arranged on one side of the second connecting mechanism away from the connecting trolley frame and used for fixing the second connecting mechanism to the transport trolley. The application can complete the disconnection and connection of the steel wire rope and the transport trolley underwater, thereby improving the operation efficiency of the equipment while ensuring the reliability.

Description

Technical Field

[0001] This application relates to the field of nuclear technology, specifically to a fuel transfer device with an underwater connection mechanism and an emergency unlocking mechanism. Background Technology

[0002] The fuel transfer unit is a key piece of equipment for loading and unloading nuclear fuel at nuclear power plants. During the loading and unloading process at nuclear power plants, the fuel transfer unit transports new fuel assemblies from the fuel building to the reactor building underwater via transport trolleys, and also transports spent fuel assemblies from the reactor building to the fuel building.

[0003] During nuclear power plant overhauls, fuel loading and unloading are the main operations, and the time taken for these operations directly determines the overhaul period, significantly impacting the economic viability of the nuclear power plant. In a certain nuclear power plant model, the fuel transfer device's transport trolley uses a dual-drive rack and pinion system. Both the fuel building and reactor building have a drive mechanism. The drive mechanism has a motor reducer mounted above water, connected to the underwater drive gear via a transmission shaft and universal joint. The transport trolley is equipped with a rack. When the trolley moves from the fuel building to the reactor building, it is first driven by the drive mechanism on the fuel building side, and then by the reactor building side, requiring a relay process. To ensure stable relay, the drive gear is equipped with a clutch relay device (CN103089952B). Due to the clutch, the driving force of the drive gear on the transport trolley is unidirectional, necessitating a counterweight system, as disclosed in prior art CN107195349B, which describes a new fuel transfer... The manual emergency mechanism of the transport unit integrates a counterweight system and a manual emergency mechanism. When the trolley is running from the fuel building side to the reactor building side, the trolley is driven by the counterweight system, and the drive gear controls the speed. The above drive scheme has the following shortcomings: First, the relay drive process needs to be carried out at low speed to ensure safety, which seriously affects the operating efficiency of the transport trolley and increases the loading and unloading time. Second, within the 60-year lifespan of the fuel transfer unit, wear and track deformation will lead to increased resistance. When the fuel transfer unit transport trolley runs from the reactor building to the fuel building, the driving force provided by the counterweight system is insufficient, and even jamming may occur. Third, the drive mechanism has a complex structure with many underwater components and insufficient reliability. Once a failure occurs, drainage is required for repair, which will greatly increase the loading and unloading time.

[0004] Existing technology CN104464857B discloses a fuel transfer device driven by a bidirectional servo motor and wire rope. However, this solution involves rigid connections between the wire ropes on both sides and the transport trolley, requiring a continuous connection between the reactor building and the fuel building. It fails to consider the need to close the manual gate valve after unloading during power plant overhauls. At this time, the fuel transfer device is underwater, making it impossible for personnel to manually disconnect the wire ropes and close the manual gate valve. During overhauls, the manual gate valve needs to be closed, and the fuel transfer device is parked in the fuel building. After the overhaul, it needs to be refueled, during which time the fuel transfer device remains underwater. This solution also fails to address the issue of reconnecting the transport trolley and the reactor-side building wire ropes. In conclusion, this solution does not meet the actual operational requirements of nuclear power plants.

[0005] To address the shortcomings of conventional fuel transfer devices, this patent invention provides a fuel transfer device with an underwater connection mechanism and an emergency unlocking mechanism. This device can disconnect and connect the wire rope to the transfer trolley underwater, improving the operating efficiency of the equipment while ensuring reliability. Summary of the Invention

[0006] The purpose of this application is to solve the aforementioned technical problems.

[0007] To achieve the above objectives, the first aspect of this application proposes a fuel transfer device with an underwater connection mechanism and an emergency unlocking mechanism, including a track, a transfer channel, and a transport trolley. The transfer channel and part of the track are located between the reactor building and the fuel building. The transport trolley is located on the track. The device also includes: a connecting frame, located on the track and closer to the reactor building than the transport trolley; a first connecting mechanism, fixed to the side of the connecting frame near the transport trolley; a second connecting mechanism, located on the side of the transport trolley near the connecting frame, which engages with the first connecting mechanism; and an emergency unlocking mechanism, located on the side of the second connecting mechanism away from the connecting frame, for fixing the second connecting mechanism to the transport trolley.

[0008] The first connecting mechanism is provided with a first locking part, which has an opening and a semi-cylindrical rotatable first locking block inside; the second connecting mechanism is provided with a second locking part, which has an opening and a semi-cylindrical rotatable second locking block inside; when the second connecting mechanism docks with the first connecting mechanism, the first locking part pushes the second locking block to rotate, and after docking is completed, the second locking block resets, and the second connecting mechanism and the first connecting mechanism form a locking connection.

[0009] Furthermore, the first connecting mechanism includes a first housing, a first lever mounting groove is provided on the side of the first housing, a first positioning shaft and a first locking head are provided at the end of the first housing near the second connecting mechanism, and a first sliding groove is provided on the first locking head to cooperate with the second locking head in the second connecting mechanism.

[0010] Furthermore, the first connecting mechanism also includes a first lever, which extends from inside the first housing through a first lever mounting groove to the outside of the first housing. The other end of the first lever is provided with a first locking block, which is connected to a first positioning shaft and rotates around the first positioning shaft.

[0011] Furthermore, the first locking block has a semi-cylindrical structure, and a second sliding groove is provided on the first locking block to cooperate with the second positioning shaft in the second connecting mechanism. The first locking head is provided with an arc-shaped opening near the first positioning shaft to cooperate with the rotation of the first locking block.

[0012] Furthermore, the first connecting mechanism also includes a first return spring, one end of which is connected to the first lever, and the other end of which is connected to the inside of the first housing away from the first lever.

[0013] Furthermore, the second connecting mechanism includes a second housing, a second lever mounting groove is provided on the side of the second housing, a second positioning shaft and a second locking head are provided at one end of the second housing near the first connecting mechanism, and a third sliding groove is provided on the second locking head to cooperate with the first locking head in the first connecting mechanism.

[0014] Furthermore, the second connecting mechanism also includes a second lever, which extends from inside the second housing through a second lever mounting groove to the outside of the second housing. The other end of the second lever is provided with a second locking block, which is connected to a second positioning shaft and rotates around the second positioning shaft.

[0015] Furthermore, the second locking block has a semi-cylindrical structure, and a fourth sliding groove is provided on the second locking block to cooperate with the first positioning shaft in the first connecting mechanism. The second locking head is provided with an arc-shaped opening near the second positioning shaft to cooperate with the rotation of the second locking block.

[0016] Furthermore, the second connecting mechanism also includes a second return spring, one end of which is connected to the second lever, and the other end of which is connected to the side of the second housing away from the second lever.

[0017] Furthermore, the emergency unlocking mechanism includes a slide rail, a fixed block, and a movable block. The slide rail is located on both sides of the second connecting mechanism and is used to guide the second connecting mechanism to move along the direction of the track. The fixed block and the movable block are located on the side of the slide rail away from the first connecting mechanism. A connecting block is located on the side of the second connecting mechanism away from the connecting frame. The connecting block and the movable block are provided with mutually cooperating protrusions and grooves, and the position of the second connecting mechanism is fixed by the fixed block and the movable block.

[0018] Furthermore, the emergency unlocking mechanism also includes a locking rod and a third return spring. The movable block is provided with a rotating shaft that is fixedly connected to the transport trolley. The transport trolley is provided with a boss. The locking rod is movably connected to the boss. One end of the locking rod contacts the movable block, and the other end of the locking rod is connected to a steel wire rope. The steel wire rope is fixed by a breaking pin and wound around the sliding rod. One end of the third return spring is connected to the end of the boss away from the second connecting mechanism along the track direction, and the other end of the third return spring is connected to the side of the movable block away from the second connecting mechanism.

[0019] Furthermore, a limiting mechanism and an unlocking unit are installed on the track near the transfer channel on one side of the reactor building. The limiting mechanism includes a first fixed rod and a first sleeve. The first sleeve is fitted onto the first fixed rod and a baffle is fixed to the first sleeve. The baffle restricts the connecting car frame to the side near the transfer channel. The unlocking unit includes a second fixed rod and a second sleeve. The second sleeve is fitted onto the second fixed rod and an extension plate is fixed to the second sleeve. An unlocking rod is provided at the end of the extension plate away from the second sleeve. The unlocking unit is closer to the transfer channel than the limiting mechanism and unlocks the first and second connecting mechanisms by means of the unlocking rod.

[0020] Furthermore, it also includes a connecting drive mechanism, located on one side of the fuel plant near the transfer channel, including an upper drive mechanism, a drive rod, and a lower transmission mechanism. The upper drive mechanism is connected to the lower transmission mechanism via the drive rod, and the drive gear shaft of the lower transmission mechanism can be vertically raised and lowered.

[0021] Furthermore, it also includes a first motor drum wire rope system located on one side of the reactor building and a second motor drum wire rope system located on one side of the fuel building. The first motor drum wire rope system is connected to the connecting frame via wire rope, and the second motor drum wire rope system is connected to the transport trolley via wire rope.

[0022] Furthermore, it also includes a counterweight system located on one side of the fuel plant. The counterweight in the counterweight system is suspended on a wire rope via a movable pulley. One end of the wire rope of the movable pulley is connected to a manual winch, and the other end of the wire rope of the movable pulley is connected to a second connecting mechanism via a fixed pulley.

[0023] By applying the above-described technical solution of the present invention, at least the following technical effects are achieved: 1. By setting up an underwater connection mechanism and an emergency unlocking mechanism, and in conjunction with a switchable dual-motor drum wire rope drive system, reliable automatic connection / disconnection, contactless power transmission, and rapid disconnection in emergency situations are achieved for the fuel transfer device in an underwater environment. This completely solves the problems of low efficiency of traditional gear and rack relay drive, easy jamming of the counterweight system, and numerous underwater components that are difficult to maintain. It significantly improves fuel transfer efficiency and system reliability, while meeting the underwater operation requirements after the manual gate valve is closed during nuclear power plant overhauls. This provides a brand-new high-safety and high-efficiency solution for the fuel transfer system of pressurized water reactor nuclear power plants. 2. Through the coordinated design of the underwater connection mechanism and the emergency unlocking mechanism, the automatic mechanical locking and remote emergency disconnection of the transport trolley and the connecting frame are realized in a completely underwater environment. The connection / disconnection operation can be completed without drainage or manual underwater operation. Among them, the breaking pin can reliably break and release automatically, ensuring millisecond-level emergency disconnection in the event of sudden failure or safety risk, significantly improving the inherent safety of the system and avoiding the risk of reactor delay due to jamming. 3. The traditional underwater gear rack clutch and counterweight system is eliminated and replaced with a new structure of double-sided wire rope traction + limit mechanism + connection mechanism, which greatly reduces the number of underwater moving parts, avoids frequent failures and drainage maintenance requirements caused by wear of drive shaft, universal joint and underwater gear, reduces maintenance costs and construction period, extends equipment life cycle and meets the "low maintenance and high reliability" operation requirements of nuclear power plants within the 60-year design life. 4. By installing a motor-driven steel wire rope system with switchable "speed control mode" and "torque control mode" on both sides of the fuel plant and reactor plant, intelligent distribution of driving force is achieved during the bidirectional operation of the transport trolley: the torque mode provides stable tension to prevent impact during acceleration / deceleration, and the speed mode achieves precise speed control during constant speed, which greatly improves the smoothness of operation and transportation efficiency.

[0024] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0025] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of a fuel transfer device with an underwater connection mechanism and an emergency unlocking mechanism according to one embodiment is shown; Figure 2 A structural schematic diagram of the first connecting mechanism in one embodiment is shown; Figure 3A structural schematic diagram of the second connecting mechanism in one embodiment is shown; Figure 4 A schematic diagram of the engagement connection between the first connecting mechanism and the second connecting mechanism in one embodiment is shown; Figure 5 A schematic diagram of the emergency unlocking mechanism in one embodiment is shown; Figure 6 A schematic diagram of the unlocking unit and the limiting mechanism in one embodiment is shown; Figure 7 A schematic diagram of the unlocking unit being lifted in one embodiment is shown; Figure 8 A schematic diagram of the structure of the drive mechanism from one perspective in one embodiment is shown; Figure 9 A structural schematic diagram of the connecting drive mechanism from another perspective is shown in one embodiment; Figure 10 A schematic diagram of the counterweight system in one embodiment is shown.

[0026] Reference numerals: 1. Track; 2. Transport trolley; 3. Connecting frame; 4. First connecting mechanism; 41. First housing; 411. First lever mounting slot; 412. First positioning shaft; 413. First locking head; 414. First slide groove; 42. First lever; 421. First locking block; 422. Second slide groove; 43. First return spring; 5. Second connecting mechanism; 51. Second housing; 511. Second lever mounting slot; 512. Second positioning shaft; 513. Second locking head; 514. Third slide groove; 52. Second lever; 521. Second locking block; 522. Fourth slide groove; 53. Second return spring; 54. Connecting block; 6. Emergency unlocking mechanism; 61. Slide rail; 62. Fixed block; 63. Movable block; 631. Rotating shaft; 64. Locking rod; 65. Third return spring; 66. Boss; 67. Steel wire rope; 68. Sliding rod; 69. Breaking pin; 7. Transfer channel; 8. Limiting mechanism; 81. First fixing rod; 82. First sleeve; 83. Baffle; 9. Unlocking unit; 91. Second fixing rod; 92. Second sleeve; 93. Extension plate; 94. Unlocking rod; 10. Connecting drive mechanism; 101. Upper drive mechanism; 102. Drive rod; 103. Lower transmission mechanism; 11. First motor drum steel wire rope system; 12. Second motor drum steel wire rope system; 13. Counterweight system; 131. Fixed pulley; 132. Moving pulley; 133. Counterweight block; 14. Manual gate valve; 15. Reactor building internal component storage pool; 16. Fuel building transfer compartment water pool. Detailed Implementation

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] The present invention will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed by the present invention.

[0029] According to one aspect of the present invention, a fuel transfer device with an underwater connection mechanism and an emergency unlocking mechanism is provided, such as... Figure 1 As shown, the system includes a track 1, a transfer channel 7, and a transport trolley 2. The transfer channel 7 and part of the track 1 are located between the reactor building and the fuel building. The transport trolley 2 is mounted on the track 1. The system also includes: a connecting frame 3, which is mounted on the track 1 and is closer to the reactor building than the transport trolley 2; a first connecting mechanism 4, which is fixed to the side of the connecting frame 3 near the transport trolley 2; a second connecting mechanism 5, which is located on the side of the transport trolley 2 near the connecting frame 3, and the second connecting mechanism 5 and the first connecting mechanism 4 form a locking connection when they are docked; and an emergency unlocking mechanism 6, which is located on the side of the second connecting mechanism 5 away from the connecting frame 3, and is used to fix the second connecting mechanism 5 to the transport trolley 2.

[0030] Specifically, in this embodiment, tracks 1 are respectively installed at the bottom of the reactor building internal components storage pool 15, the transfer channel, and the bottom of the fuel building transfer tank pool 16. A transport trolley 2 is installed on the fuel building side, the trolley 2 having a rack and pinion mechanism, and can run on the three sections of tracks 1. The length of the transport trolley 2 is longer than the transfer channel 7. A connecting frame 3 is installed on the reactor building side, and the connecting frame 3 can run on the three sections of tracks 1. A first connecting mechanism 4 is fixed to the connecting frame 3, and a second connecting mechanism 5 is installed on the transport trolley 2, the second connecting mechanism 5 being fixed by an emergency unlocking mechanism 6.

[0031] Furthermore, the first connecting mechanism 4 is provided with a first locking part, the first locking part has an opening, and a semi-cylindrical rotatable first locking block 421 is provided inside the first locking part; the second connecting mechanism 5 is provided with a second locking part, the second locking part has an opening, and a semi-cylindrical rotatable second locking block 521 is provided inside the second locking part; when the second connecting mechanism 5 docks with the first connecting mechanism 4, the first locking part pushes the second locking block 521 to rotate, after docking is completed, the second locking block 521 is reset, and the second connecting mechanism 5 and the first connecting mechanism 4 form a snap-fit ​​connection.

[0032] Furthermore, such as Figure 2As shown, the first connecting mechanism 4 includes a first housing 41. The first housing 41 has a first lever mounting groove 411 on its side. The first housing 41 has a first positioning shaft 412 and a first locking head 413 at one end near the second connecting mechanism 5. The first locking head 413 has a first sliding groove 414 that cooperates with the second locking head 513 in the second connecting mechanism 5.

[0033] Specifically, in this embodiment, the end of the first locking head 413 near the second connecting mechanism 5 is a pyramidal structure with rounded corners at the top.

[0034] Furthermore, such as Figure 2 As shown, the first connecting mechanism 4 also includes a first lever 42. The first lever 42 extends from the inside of the first housing 41 through the first lever mounting groove 411 to the outside of the first housing 41. The other end of the first lever 42 is provided with a first locking block 421. The first locking block 421 is connected to the first positioning shaft 412 and rotates around the first positioning shaft 412.

[0035] When the first connecting mechanism 4 mates with the second connecting mechanism 5, the second locking head 513 of the second connecting mechanism 5 slides along the first sliding groove 414 on the first locking head 413 and pushes the first locking block 421 to rotate. Since the first lever 42 extends from the inside of the first housing 41 through the first lever mounting groove 411 to the outside of the first housing 41, and the other end is connected to the first locking block 421, and the first locking block 421 is connected to the first positioning shaft 412 and can rotate around it, the first locking block 421 rotates under the drive of the second connecting mechanism 5, and drives the first lever 42 to move, so that the first locking block 421 is engaged in the corresponding limiting structure of the second connecting mechanism 5. Once fully engaged, the first lever 42 resets under the action of the first return spring 43, and drives the first locking block 421 to reset, thus achieving automatic locking between the first connecting mechanism 4 and the second connecting mechanism 5. This structure utilizes the principle of mechanical levers, enabling locking without external power in an underwater environment, effectively resisting the risk of loosening caused by water flow disturbance and mechanical vibration, and ensuring the reliability of the connection. At the same time, the first lever mounting groove 411 provides limit and guidance for the first lever 42, ensuring its rotation trajectory is stable. The first positioning shaft 412 serves as a rotation fulcrum, ensuring that the first locking block 421 always completes the locking action at a precise angle, improving the repeatability and stability of the docking process.

[0036] like Figure 4 The image shows the state after the first and second connecting mechanisms are engaged and connected.

[0037] Furthermore, such as Figure 2As shown, the first locking block 421 has a semi-cylindrical structure. The first locking block 421 is provided with a second sliding groove 422 that cooperates with the second positioning shaft 512 in the second connecting mechanism 5. The first locking head 413 is provided with an arc-shaped opening that cooperates with the rotation of the first locking block 421 near the first positioning shaft 412.

[0038] The first locking block 421 has a semi-cylindrical structure, and its outline shape forms a precise guiding fit with the second positioning shaft 512 in the second connecting mechanism 5. When the first locking block 421 rotates around the first positioning shaft 412, the second positioning shaft 512 slides along the second sliding groove provided on the first locking block 421, ensuring that the movement trajectory during the rotation is stable and controllable, and avoiding jamming or offset caused by mismatch in structural shape. At the same time, the first locking head 413 is provided with an arc-shaped opening near the first positioning shaft 412, providing sufficient clearance for the rotation path of the first locking block 421, so that the first locking block 421 will not interfere with the first locking head 413 during rotation, thereby ensuring the reliable engagement and disengagement of the first connecting mechanism 4 and the second connecting mechanism 5 in the underwater environment, significantly improving the docking stability and emergency unlocking response reliability of the connecting mechanism under complex working conditions.

[0039] Furthermore, such as Figure 3 As shown, the first connecting mechanism 4 also includes a first return spring 43, one end of which is connected to the first lever 42, and the other end of which is connected to the inside of the first housing 41 on the side away from the first lever 42.

[0040] In other embodiments, the shape of the first locking head can be designed in various ways according to the force application method and the mating space. The first locking head can be an arc-shaped protrusion structure, a wedge-shaped inclined surface structure, a frustum-shaped structure, a spherical boss structure, a stepped transition structure, or a columnar structure with guide chamfers, so as to form a progressive force during the docking process, thereby reducing assembly resistance and improving the smoothness of rotation drive. The force-bearing surface of the first locking head can be a continuous curved surface, a polygonal surface, or a composite curved surface structure. The first locking block can be a hemispherical, cylindrical sector, wedge-shaped block, eccentric cylinder, polygonal prism (such as a triangular prism, a square prism, or a hexagonal prism), a cam-shaped structure with a curved transition, or an eccentric cam structure with an asymmetrical profile. The outer peripheral profile of the first locking block can be set as an involute curved surface, a hyperbolic transition surface, or a combination of circular arc surfaces to improve the contact state and force distribution during rotation.

[0041] Furthermore, the second connecting mechanism 5 includes a second housing 51, a second lever mounting groove 511 is provided on the side of the second housing 51, a second positioning shaft 512 and a second locking head 513 are provided at one end of the second housing 51 near the first connecting mechanism 4, and a third sliding groove 514 is provided on the second locking head 513 to cooperate with the first locking head 413 in the first connecting mechanism 4.

[0042] Furthermore, the second connecting mechanism 5 also includes a second lever 52, which extends from inside the second housing 51 through the second lever mounting groove 511 to the outside of the second housing 51. The other end of the second lever 52 is provided with a second locking block 521, which is connected to the second positioning shaft 512 and rotates around the second positioning shaft 512.

[0043] Furthermore, the second locking block 521 has a semi-cylindrical structure, and the second locking block 521 is provided with a fourth sliding groove 522 that cooperates with the first positioning shaft 412 in the first connecting mechanism 4. The second locking head 513 is provided with an arc-shaped opening that cooperates with the rotation of the second locking block 521 near the second positioning shaft 512.

[0044] Furthermore, the second connecting mechanism 5 also includes a second return spring 53, one end of which is connected to the second lever 52, and the other end of which is connected to the inside of the second housing 51 on the side away from the second lever 52.

[0045] In other embodiments, the shape of the second locking head can be designed in various ways according to the force application method and the mating space. The second locking head can be an arc-shaped protrusion structure, a wedge-shaped inclined surface structure, a frustum-shaped structure, a spherical boss structure, a stepped transition structure, or a columnar structure with guide chamfers, so as to form a progressive force during the docking process, thereby reducing assembly resistance and improving the smoothness of rotation drive. The force-bearing surface of the second locking head can be a continuous curved surface, a polygonal surface, or a composite curved surface structure. The second locking block can be a hemispherical, cylindrical sector, wedge-shaped block, eccentric cylinder, polygonal prism (such as a triangular prism, a square prism, or a hexagonal prism), a cam-shaped structure with a curved transition, or an eccentric cam structure with an asymmetrical profile. The outer peripheral profile of the second locking block can be set as an involute curved surface, a hyperbolic transition surface, or a combination of circular arc surfaces to improve the contact state and force distribution during rotation.

[0046] Furthermore, such as Figure 5As shown, the emergency unlocking mechanism 6 includes a slide rail 61, a fixed block 62, and a movable block 63. The slide rail 61 is located on both sides of the second connecting mechanism 5 and is used to guide the second connecting mechanism 5 to move along the direction of the track 1. The fixed block 62 and the movable block 63 are located on the side of the slide rail 61 away from the first connecting mechanism 4. A connecting block 54 is located on the side of the second connecting mechanism 5 away from the connecting frame 3. The connecting block 54 and the movable block 63 are provided with mutually cooperating protrusions and grooves, and the position of the second connecting mechanism 5 is fixed by the fixed block 62 and the movable block 63.

[0047] The second connecting mechanism 5 is precisely guided to move along the direction of track 1 by slide rails 61 set on both sides, ensuring stable alignment with the first connecting mechanism 4 when docking. Under normal circumstances, the connecting block 54 and the movable block 63 are mechanically locked by the interlocking of protrusions and grooves. The fixed block 62 acts as a limiting support structure and works in conjunction with the movable block 63 to firmly fix the connecting block 54, thereby reliably maintaining the axial positioning of the second connecting mechanism 5 under underwater high pressure, vibration or water flow impact. When emergency unlocking is triggered, the movable block 63 can rotate along a predetermined path to release the interlocking relationship between the protrusions and grooves, allowing the second connecting mechanism 5 to slide freely away along the direction of track 1 under the guidance of slide rails 61, achieving controllable and rapid underwater emergency separation, effectively solving the technical defects of unreliable locking and uncontrollable release in the original structure.

[0048] Furthermore, such as Figure 5 As shown, the emergency unlocking mechanism 6 also includes a locking rod 64 and a third return spring 65. The movable block 63 is provided with a rotating shaft 631 fixedly connected to the transport trolley 2. The transport trolley 2 is provided with a boss 66. The locking rod 64 is movably connected to the boss 66. One end of the locking rod 64 contacts the movable block 63, and the other end of the locking rod 64 is connected to a wire rope 67. The wire rope 67 is fixed by a breaking pin 69 and wound around the sliding rod 68. One end of the third return spring 65 is connected to the end of the boss 66 away from the second connecting mechanism 5 along the track direction, and the other end of the third return spring 65 is connected to the side of the movable block 63 away from the second connecting mechanism 5.

[0049] It is important to note that Figure 5 The structure of the second connecting mechanism 5 shown is a simplified schematic.

[0050] Under normal operating conditions, the locking rod 64 restricts the movable block 63 from rotating around the rotation axis 631, keeping the groove of the movable block 63 engaged with the protrusion of the connecting block 54, thereby ensuring that the second connecting mechanism 5 is stably fixed to the lower part of the transport trolley 2. In the event of an underwater emergency, the externally applied tension exceeds the preset breaking strength of the breaking pin 69, causing the breaking pin 69 to break, the wire rope 67 to lose its tension constraint, and the locking rod 64 to disengage from the boss 66 after losing its limit. The movable block 63 rotates around the rotation axis 631 under the elastic force of the third return spring 65, causing the groove to disengage from the protrusion of the connecting block 54. The second connecting mechanism 5 loses its fixed constraint and can slide freely away from the transport trolley 2 along the slide rail 61, achieving rapid and reliable underwater emergency separation.

[0051] Furthermore, such as Figure 6 As shown, a limiting mechanism 8 and an unlocking unit 9 are installed on the track 1 on one side of the reactor building, near the transfer channel 7. The limiting mechanism 8 includes a first fixing rod 81 and a first sleeve 82. The first sleeve 82 is fitted onto the first fixing rod 81 and is fixed with a baffle 83, which restricts the connecting frame 3 to the side near the transfer channel 7. The unlocking unit 9 includes a second fixing rod 91 and a second sleeve 92. The second sleeve 92 is fitted onto the second fixing rod 91 and is fixed with an extension plate 93. An unlocking rod 94 is provided at the end of the extension plate 93 away from the second sleeve 92. The unlocking unit 9 is closer to the transfer channel 7 than the limiting mechanism 8, and the first connecting mechanism 4 and the second connecting mechanism 5 are unlocked by the unlocking rod 94. Specifically, in this embodiment, a limiting mechanism 8 is provided on the reactor building side. The limiting mechanism 8 can be lifted or lowered by a steel wire rope. When lifted, the limiting mechanism 8 can restrict the position of the connecting frame 3 on the reactor side track near the transfer channel.

[0052] like Figure 7 As shown, when the first sleeve 82 in the limiting mechanism 8 is lifted, its structure acts on the connecting frame 3, precisely limiting it to the side closer to the transfer channel 7. This ensures that the connecting frame 3 can be stably positioned in the underwater environment without manual intervention, providing a reliable prerequisite for the precise docking of the first connecting mechanism 4 and the second connecting mechanism 5. At the same time, the unlocking unit 9 is located on the side of the limiting mechanism 8 closer to the transfer channel 7. When the second sleeve 92 is lifted, the unlocking rod 94 can trigger the unlocking mechanism inside the first connecting mechanism 4, reliably separating the engagement between the second connecting mechanism 5 and the first connecting mechanism 4. This structural design allows the entire unlocking process to be carried out entirely on water without the need for personnel to enter the underwater environment, significantly improving the safety and reliability of the operation.

[0053] Furthermore, such as Figure 8 and Figure 9As shown, the fuel transfer device also includes a connecting drive mechanism 10, which is located on one side of the fuel plant near the transfer channel 7. It includes an upper drive mechanism 101, a drive rod 102, and a lower transmission mechanism 103. The upper drive mechanism 101 is connected to the lower transmission mechanism 103 through the drive rod 102. The drive gear shaft of the lower transmission mechanism 103 can be vertically raised and lowered.

[0054] Specifically, in this embodiment, a connecting drive mechanism 10 is installed on the fuel plant side, spanning above the transfer compartment. The connecting drive mechanism 10 is integrally connected to an upper drive mechanism, a drive rod, and a lower transmission mechanism. The upper drive mechanism transmits power to the lower transmission mechanism via the drive rod. The lower transmission mechanism's drive gear meshes with the rack of the transport trolley, transmitting driving force to the transport trolley. The drive gear shaft of the lower transmission mechanism can be raised and lowered, thereby realizing the meshing and disengagement of the drive gear and the rack of the transport trolley.

[0055] After the transport trolley 2 and the connecting frame 3 are engaged and connected through the first connecting mechanism 4 and the second connecting mechanism 5, the drive gear shaft can be lowered vertically to disengage the drive gear of the lower transmission mechanism from the rack of the transport trolley 2. This releases the driving force constraint of the connecting drive mechanism 10 on the transport trolley 2, so that the transport trolley 2 is no longer subject to mechanical interference from the drive gear during subsequent transfer. It can move freely without power traction by the external wire rope system, effectively solving the problem of limited transfer caused by continuous engagement of the drive mechanism in the underwater environment.

[0056] Furthermore, such as Figure 1 As shown, the fuel transfer device also includes a first motor drum wire rope system 11 located on one side of the reactor building and a second motor drum wire rope system 12 located on one side of the fuel building. The first motor drum wire rope system 11 is connected to the connecting frame 3 via wire rope, and the second motor drum wire rope system 12 is connected to the transport trolley 2 via wire rope.

[0057] Specifically, in this embodiment, both the first motor drum wire rope system 11 and the second motor drum wire rope system 12 can be switched to speed control mode and torque control mode respectively according to the running direction.

[0058] This configuration allows the connecting frame 3 and the transport trolley 2 to be precisely controlled by their respective independent drive systems in an underwater environment, achieving stable towing and positioning before docking and avoiding the offset or impact caused by linkage traction in traditional single drive methods. After the first connecting mechanism 4 and the second connecting mechanism 5 are engaged, the two systems can still maintain independent tension adjustment capabilities to ensure dynamic stability of the connection state. In an emergency, after the second connecting mechanism 5 is released by the emergency unlocking mechanism 6, the first motor drum wire rope system 11 and the second motor drum wire rope system 12 can move in opposite directions respectively, realizing the rapid separation and safe evacuation of the connecting frame 3 and the transport trolley 2, significantly improving the safety and controllability of the underwater fuel transfer process.

[0059] Furthermore, such as Figure 10 As shown, the fuel transfer device also includes a counterweight system 13 located on one side of the fuel plant. The counterweight block 133 in the counterweight system 13 is suspended on the wire rope 67 by a movable pulley 132. The wire rope 67 at one end of the movable pulley 132 is connected to a manual winch, and the wire rope 67 at the other end of the movable pulley 132 is connected to the second connecting mechanism 5 by a fixed pulley 131.

[0060] Specifically, in this embodiment, a counterweight system 13 is installed on the fuel plant side. The counterweight is suspended from a wire rope via a movable pulley. The fixed end of the wire rope is connected to a manual winch, and the movable end is connected to a second connecting mechanism 5. Under normal operation, the counterweight moves up and down with the trolley. When the movable pulley reaches its top, it can be fixed by a fixing pin, becoming a fixed pulley.

[0061] The process of the technical solution of this application is described below.

[0062] When the fuel transfer unit is in a parked state, the transport trolley 2 is positioned on track 1 on the fuel building side, and the connecting frame 3 is positioned on track 1 on the reactor building side. The drive gear shaft of the lower transmission mechanism of the connecting drive mechanism 10 is in a raised state, and the drive gear meshes with the rack of the transport trolley 2. Before loading and unloading, the connecting drive mechanism 10 drives the transport trolley 2 to move along track 1 towards the reactor building side until the second connecting mechanism 5 at the bottom of the transport trolley 2 aligns with the first connecting mechanism 4 at the bottom of the connecting frame 3.

[0063] After connection, the drive gear shaft of the connecting drive mechanism 10 is lowered using a long-handled tool, causing the drive gear to disengage from the rack of the transport trolley 2, thus releasing the driving force constraint of the connecting drive mechanism 10 on the transport trolley 2. Subsequently, the limit mechanism 8 is released through the waterborne operating platform to release the limit on the connecting frame 3, allowing the transport trolley 2 to move freely on the three-section track 1. The transport trolley 2 is then towed to the end position of the fuel plant by the second motor drum wire rope system 12, thus completing the preparations before loading and unloading.

[0064] When the fuel transfer device is in operation, as the transport trolley 2 moves towards the reactor building, the first motor drum wire rope system 11 switches to speed control mode, providing driving force and controlling the speed of the transport trolley 2, while the second motor drum wire rope system 12 switches to torque control mode, providing constant tension to ensure the smooth operation of the transport trolley 2.

[0065] After the loading and unloading operations are completed, the transport trolley 2 needs to be separated from the connecting frame 3 and reset. At this time, the unlocking unit 9 is lifted by the wire rope, and the first motor drum wire rope system 11 is used to drag the transport trolley 2 towards the reactor building side until the unlocking unit 9 moves the first lever 42 to the unlocking position. At this time, the first connecting mechanism 4 and the second connecting mechanism 5 are separated, the transport trolley 2 is separated from the connecting frame 3, the first motor drum wire rope system 11 stops, and the second motor drum wire rope system 12 is used to drag the transport trolley 2 back to the end position of the fuel building. The drive gear of the connecting drive mechanism 10 is raised. On the reactor building side, the limit mechanism 8 is raised, the unlocking unit 9 is lowered, and the first motor drum wire rope system 11 is used to drag the connecting frame 3 to the limit position. At this time, the fuel transfer device returns to the parking state, the manual gate valve 14 is closed, and the isolation between the reactor building and the fuel building is completed.

[0066] In case of an emergency underwater separation, the movable pulley of the emergency unlocking mechanism 6 is lifted to a fixed position and secured. The emergency wire rope is pulled by a manual winch. Once the tension of the wire rope exceeds the tension of the break pin 69, the break pin 69 is broken. The wire rope continues to pull out the locking rod 64. The movable block 63 rotates around the rotating shaft 631 under the elastic force of the third return spring 65. The second connecting mechanism 5 is separated from the transport trolley 2, and the transport trolley 2 can be towed back to the fuel plant side. The connecting frame 3 is towed back to the reactor plant side. At this time, the manual gate valve 14 can be closed to drain the water pool of the transfer tank on the fuel plant side and perform maintenance on the fuel transfer device.

[0067] By applying the above-described technical solution of the present invention, at least the following technical effects are achieved: 1. By setting up an underwater connection mechanism and an emergency unlocking mechanism, and in conjunction with a switchable dual-motor drum wire rope drive system, reliable automatic connection / disconnection, contactless power transmission, and rapid disconnection in emergency situations are achieved for the fuel transfer device in an underwater environment. This completely solves the problems of low efficiency of traditional gear and rack relay drive, easy jamming of the counterweight system, and numerous underwater components that are difficult to maintain. It significantly improves fuel transfer efficiency and system reliability, while meeting the underwater operation requirements after the manual gate valve is closed during nuclear power plant overhauls. This provides a brand-new high-safety and high-efficiency solution for the fuel transfer system of pressurized water reactor nuclear power plants. 2. Through the coordinated design of the underwater connection mechanism and the emergency unlocking mechanism, the automatic mechanical locking and remote emergency disconnection of the transport trolley and the connecting frame are realized in a completely underwater environment. The connection / disconnection operation can be completed without drainage or manual underwater operation. Among them, the breaking pin can reliably break and release automatically, ensuring millisecond-level emergency disconnection in the event of sudden failure or safety risk, significantly improving the inherent safety of the system and avoiding the risk of reactor delay due to jamming. 3. The traditional underwater gear rack clutch and counterweight system is eliminated and replaced with a new structure of double-sided wire rope traction + limit mechanism + connection mechanism, which greatly reduces the number of underwater moving parts, avoids frequent failures and drainage maintenance requirements caused by wear of drive shaft, universal joint and underwater gear, reduces maintenance costs and construction period, extends equipment life cycle and meets the "low maintenance and high reliability" operation requirements of nuclear power plants within the 60-year design life. 4. By installing a motor-driven steel wire rope system with switchable "speed control mode" and "torque control mode" on both sides of the fuel plant and reactor plant, intelligent distribution of driving force is achieved during the bidirectional operation of the transport trolley: the torque mode provides stable tension to prevent impact during acceleration / deceleration, and the speed mode achieves precise speed control during constant speed, which greatly improves the smoothness of operation and transportation efficiency.

[0068] The above are merely several specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0070] It should be noted that, in the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. A fuel transfer device with an underwater connection mechanism and an emergency unlocking mechanism, comprising a track (1), a transfer channel (7), and a transport trolley (2), wherein the transfer channel (7) and part of the track (1) are disposed between the reactor building and the fuel building, and the transport trolley (2) is disposed on the track (1), characterized in that, Also includes: The connecting frame (3) is set on the track (1) and is closer to the reactor building than the transport trolley (2); The first connecting mechanism (4) is fixed on the side of the connecting frame (3) near the transport trolley (2); The second connecting mechanism (5) is disposed on the side of the transport trolley (2) near the connecting frame (3), and the second connecting mechanism (5) and the first connecting mechanism (4) form a snap-fit ​​connection when they dock; An emergency unlocking mechanism (6) is provided on the side of the second connecting mechanism (5) away from the connecting frame (3) for fixing the second connecting mechanism (5) to the transport trolley (2).

2. The fuel transfer device according to claim 1, characterized in that, The first connecting mechanism (4) is provided with a first locking part, the first locking part is provided with an opening, and a semi-cylindrical rotatable first locking block (421) is provided inside the first locking part; the second connecting mechanism (5) is provided with a second locking part, the second locking part is provided with an opening, and a semi-cylindrical rotatable second locking block (521) is provided inside the second locking part; when the second connecting mechanism (5) docks with the first connecting mechanism (4), the first locking part pushes the second locking block (521) to rotate. After docking is completed, the second locking block (521) is reset, and the second connecting mechanism (5) and the first connecting mechanism (4) form a snap-fit ​​connection.

3. The fuel transfer device according to claim 2, characterized in that, The first connecting mechanism (4) includes a first housing (41), a first lever mounting groove (411) is provided on the side of the first housing (41), a first positioning shaft (412) and a first locking head (413) are provided at one end of the first housing (41) near the second connecting mechanism (5), and a first sliding groove (414) is provided on the first locking head (413) to cooperate with the second locking head (513) in the second connecting mechanism (5).

4. The fuel transfer device according to claim 3, characterized in that, The first connecting mechanism (4) further includes a first lever (42), which extends from inside the first housing (41) through the first lever mounting groove (411) to the outside of the first housing (41). The other end of the first lever (42) is provided with a first locking block (421), which is connected to the first positioning shaft (412) and rotates around the first positioning shaft (412).

5. The fuel transfer device according to claim 4, characterized in that, The first locking block (421) is a semi-cylindrical structure. The first locking block (421) is provided with a second sliding groove (422) that cooperates with the second positioning shaft (512) in the second connecting mechanism (5). The first locking head (413) is provided with an arc-shaped opening that cooperates with the rotation of the first locking block (421) near the first positioning shaft (412).

6. The fuel transfer device according to claim 5, characterized in that, The first connecting mechanism (4) further includes a first return spring (43), one end of which is connected to the first lever (42), and the other end of which is connected to the side of the first housing (41) away from the first lever (42).

7. The fuel transfer device according to claim 2, characterized in that, The second connecting mechanism (5) includes a second housing (51), a second lever mounting groove (511) is provided on the side of the second housing (51), a second positioning shaft (512) and a second locking head (513) are provided at one end of the second housing (51) near the first connecting mechanism (4), and a third sliding groove (514) is provided on the second locking head (513) to cooperate with the first locking head (413) in the first connecting mechanism (4).

8. The fuel transfer device according to claim 7, characterized in that, The second connecting mechanism (5) further includes a second lever (52), which extends from inside the second housing (51) through the second lever mounting groove (511) to the outside of the second housing (51). The other end of the second lever (52) is provided with a second locking block (521), which is connected to the second positioning shaft (512) and rotates around the second positioning shaft (512).

9. The fuel transfer device according to claim 8, characterized in that, The second locking block (521) is a semi-cylindrical structure. The second locking block (521) is provided with a fourth sliding groove (522) that cooperates with the first positioning shaft (412) in the first connecting mechanism (4). The second locking head (513) is provided with an arc-shaped opening that cooperates with the rotation of the second locking block (521) near the second positioning shaft (512).

10. The fuel transfer device according to claim 9, characterized in that, The second connecting mechanism (5) further includes a second return spring (53), one end of which is connected to the second lever (52), and the other end of which is connected to the side of the second housing (51) away from the second lever (52).

11. The fuel transfer device according to claim 1, characterized in that, The emergency unlocking mechanism (6) includes a slide rail (61), a fixed block (62), and a movable block (63). The slide rail (61) is located on both sides of the second connecting mechanism (5) and is used to guide the second connecting mechanism (5) to move along the direction of the track (1). The fixed block (62) and the movable block (63) are located on the side of the slide rail (61) away from the first connecting mechanism (4). A connecting block (54) is provided on the side of the second connecting mechanism (5) away from the connecting frame (3). The connecting block (54) and the movable block (63) are provided with mutually cooperating protrusions and grooves. The position of the second connecting mechanism (5) is fixed by the fixed block (62) and the movable block (63).

12. The fuel transfer device according to claim 11, characterized in that, The emergency unlocking mechanism (6) further includes a locking rod (64) and a third return spring (65). The movable block (63) is provided with a rotating shaft (631) fixedly connected to the transport trolley (2). The transport trolley (2) is provided with a boss (66). The locking rod (64) is movably connected to the boss (66). One end of the locking rod (64) contacts the movable block (63). The other end of the locking rod (64) is connected to a wire rope (67). The wire rope (67) is fixed by a breaking pin (69) and wound around a sliding rod (68). One end of the third return spring (65) is connected to the end of the boss (66) away from the second connecting mechanism (5) along the track direction. The other end of the third return spring (65) is connected to the side of the movable block (63) away from the second connecting mechanism (5).

13. The fuel transfer device according to claim 1, characterized in that, A limiting mechanism (8) and an unlocking unit (9) are provided on the track (1) on one side of the reactor building near the transfer channel (7). The limiting mechanism (8) includes a first fixing rod (81) and a first sleeve (82). The first sleeve (82) is fitted onto the first fixing rod (81). A baffle (83) is fixed to the first sleeve (82). The baffle (83) restricts the connecting frame (3) to the side near the transfer channel (7). The unlocking unit (9) includes a second fixing rod (91) and a second sleeve (92). The second sleeve (92) is fitted onto the second fixing rod (91). An extension plate (93) is fixed to the second sleeve (92). An unlocking rod (94) is provided at the end of the extension plate (93) away from the second sleeve (92). The unlocking unit (9) is closer to the transfer channel (7) than the limiting mechanism (8). The first connecting mechanism (4) and the second connecting mechanism (5) are unlocked by the unlocking rod (94).

14. The fuel transfer device according to claim 1, characterized in that, It also includes a connecting drive mechanism (10), which is located on one side of the fuel plant near the transfer channel (7). It includes an upper drive mechanism (101), a drive rod (102), and a lower transmission mechanism (103). The upper drive mechanism (101) is connected to the lower transmission mechanism (103) through the drive rod (102). The drive gear shaft of the lower transmission mechanism (103) can be vertically raised and lowered.

15. The fuel transfer device according to claim 1, characterized in that, It also includes a first motor drum wire rope system (11) located on one side of the reactor building and a second motor drum wire rope system (12) located on one side of the fuel building. The first motor drum wire rope system (11) is connected to the connecting frame (3) by a wire rope, and the second motor drum wire rope system (12) is connected to the transport trolley (2) by a wire rope.

16. The fuel transfer device according to claim 1, characterized in that, It also includes a counterweight system (13) set on one side of the fuel plant. The counterweight block (133) in the counterweight system (13) is suspended on the wire rope (67) by a movable pulley (132). The wire rope (67) at one end of the movable pulley (132) is connected to a manual winch, and the wire rope (67) at the other end of the movable pulley (132) is connected to the second connecting mechanism (5) by a fixed pulley (131).

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